000
AXPZ20 KNHC 162117
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2205 UTC Sun Jul 16 2023

Tropical Weather Discussion for the eastern Pacific Ocean from
03.4S to 30N, east of 120W including the Gulf of California, and
from the Equator to 30N, between 120W and 140W. The following
information is based on satellite imagery, weather observations,
radar, and meteorological analysis.

Based on 1800 UTC surface analysis and satellite imagery through
2100 UTC.

...SPECIAL FEATURES...

Tropical Storm Calvin is centered near 16.1N 136.3W at 16/2100
UTC moving W at 14 kt. Estimated minimum central pressure is 996
mb. Maximum sustained wind speed is 55 kt with gusts to 65 kt.
Numerous moderate to isolated strong convection is noted within 
about 60 nm NE semicircle of center. A recent altimeter pass 
indicates seas in excess of 12 ft seas extending within 240 nm NE
quadrant of center. Maximum seas are estimated to reach 24 ft. 
On the forecast track, the center of Calvin will move into the central 
Pacific basin late tonight or early Monday and approach the Hawaiian 
Islands on Tuesday and early Wednesday. Some additional weakening is 
forecast during the next few days.  Swells generated by Calvin are 
expected to begin reaching the Hawaiian Islands during the next 
couple of days. These swells are likely to cause life-threatening
surf and rip current conditions. 

Please read the latest HIGH SEAS FORECAST issued by National 
Hurricane Center at web-site 
https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml and the latest 
T.S. Calvin Forecast/Advisory and Public Advisory at 
www.hurricanes.gov for more details. 

...TROPICAL WAVE...

A tropical wave is along 94W/95W and N of 04N, moving W at 10 to
15 kt. The wave extends northward across the Gulf of Tehuantepec.
Most of the convective activity is ahead of the wave axis, and 
covers the waters from 04N to 15N between 95W and 104W.

A second tropical wave is along 114W/115W from 04N to 18N, moving
W at 10 to 15 kt. Scattered moderate convection is observed from
08N to 11N between 106W and 120W. 

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

The monsoon trough extends from 10N84W to 09N92W. The ITCZ stretches
from 09N97W to 07N120W to beyond 07N140W. Scattered moderate to 
isolated strong convection is noted from 05N to 08N between 83W 
and 89W, from 04N to 15N between 95W and 104W, and 08N to 11N 
between 106W and 125W.

...OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

A surface ridge dominates the offshore forecast waters of Baja 
California. Under the influence of the ridge, gentle to moderate
NW winds prevail, with seas of 4 to 6 ft. Gentle to moderate 
southerly winds are noted per scatterometer data over the northern
Gulf of California where seas are in the 3 to 5 ft range based 
on altimeter data. Elsewhere across the Gulf, light to gentle 
winds and seas of 1 to 3 ft are noted. Fresh to strong northerly 
winds are seen in the Tehuantepec region and downwind to about 
15N, with seas of 4 to 6 ft. Elsewhere across the remainder of 
the Mexican offshore waters, light and variable winds and seas of
4 to 5 ft in SW swell are observed. Since this morning, an area 
of clouds, with embedded showers and thunderstorms has move from 
the northern Gulf of California across Baja California Norte into
the eastern Pacific waters.

For the forecast, the ridge will continue to dominate the offshore
forecast waters of Baja California through at least mid-week 
supporting gentle to moderate NW winds with seas in the 4 to 5 ft
range. Similar wind speeds are expected in the Gulf of California
with seas of 3 ft or less. Fresh to strong northerly winds are 
forecast to persist in the Tehuantepec region through Tue with 
seas building to 8 ft. 

...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, 
AND WITHIN 750 NM OF ECUADOR...

Fresh to strong NE to E winds prevail across the Papagayo region
and downwind to about 89W. Seas are 5 to 7 ft within these 
winds. Light to gentle winds and seas of 4 to 5 ft are noted over
the remainder of the offshore waters north of 03N. Gentle to 
moderate southerly winds are observed south of 03N where seas are
4 to 6 ft.

For the forecast, fresh to strong NE to E winds are forecast to
pulse in the Papagayo region through the middle of the week with
seas building to 8 ft. Light to gentle winds will dominate the 
remainder of the offshore forecast waters, with the exception of 
gentle to moderate southerly winds between Ecuador and the 
Galapagos Islands, and moderate to locally fresh NE to E winds 
across the offshore waters of Guatemala and El Salvador. Outside 
of the Papagayo region, seas of 4 to 5 ft in SW swell are expected.
However, seas generating in the Papagayo area will spread across
the offshore waters of Guatemala and El Salvador building seas 
to 5 to 7 ft.

...REMAINDER OF THE AREA...

Please see the SPECIAL FEATURES section above for more information
on T.S. Calvin that is moving westward toward the central Pacific
basin. 

Aside from Calvin, a ridge prevails across the north waters anchored
by a 1024 mb high pressure center located N of the area near 
37N136W. Gentle to moderate winds are noted under the influence 
of the ridge. Wind and seas could be higher near the convective 
activity along the ITCZ/Monsoon Trough.

For the forecast, Calvin will move to 16.5N 138.8W Mon morning, and
will be W of area near 17.1N 142.3W on Mon afternoon. Seas in excess
of 8 ft generating by Calvin, will continue to propagate across the
open waters, covering the area W of a line from 22N140W to 19N137W
to 14N140W by Mon afternoon. By Wed, an area of fresh to strong
E winds, with seas to 8 or 9 ft could develop to the S and SW of
the Tehuantepec region in association with a developing low pressure
along the monsoon trough. 

$$
GR